Electric water-heater.



No. 738,607.. 4 PATENTED SEPT. a, 1903..

' J. W. EWART.

ELECTRIC WATER HEATER.

APPLICATION rum) H11. 3, 1903'. no 11911111.. 2 sums-sum 1.

M WM

No. 738,607. PATBNTED SEPT. 8, 1903,

J. w. EWART.

ELECTRIC WATER HEATER.

APPLICATION FILED JAN. 3, 1903.

10 MODEL. 2 SHEETS-SHEET 2 UNITED STATES Patented September 8, 1903.

JOHN IVILLIAM EWART, OF VVENDOVER, ENGLAND.

ELECTRIC WATER-HEATER.

SPECIFICATION forming part'of Letters Patent No. 73$,607,

dated September 8, 1903.

Application filed January 3,1903. Serial No. 137,681. (No model.)

To aZZ whom it may concern:

Beit known that 1, JOHN WILLIAM EWART, a subject of the King of Great Britain, residing at Surrey House, Chiltern Road,Wendover, in the county of Bucks, England, have invented new and useful Improvements in Electric Water-Heaters, of which the following is a specification.

This invention relates to improvements in electric water-heaters.

According to this invention I construct the improved heater of a number of tubes having a covering of some suitable insulating material-such as mica, enamel, or the likethrough which the water to be heated flows and around the insulation of which is coiled or wound a wire or wires, through which an electric current is caused to flow. The tube or tubes is or are arranged in an air-tight jacket or casing from which the air is withdrawn, so as to leave the tubes and wires in a practical vacuum, the inlet and outlet openings in the casing for the water-tubes and wires being hermetically sealed, or I may construct the heater with water jackets or partitions in place of a tube or tubes, .having a wire or wires coiled around or passing up and down lengthwise of the jackets or partitions, the whole being inolosed and arranged in an air-tight casing, as described.

To use the apparatus, water is caused to flow through the system of tubesor jackets and current through the wires surrounding or passing up and down legthwise of them, so as to bring the said wires to a bright-red heat, a temperature rendered possible by the absence of air from the casing.

To enable the invention to be fully understood, I will describe it by reference to the accompanying drawings, in which- Figure 1 is a sectional elevation of a waterheater made according to the invention. Fig. 2 is a similar view of a modified form of heater. Fig. 3 is a sectional elevation of a construction of the apparatus having inter nal water-jackets or partitions. Fig. 4 is a section on the line 4 4, Fig. 3.

Referring first to the arrangement shown in Fig. 1, Ct represents the tube, which is here shown of a zigzag shape and which is connected to the water-jacket b by the pipe or nipple c and which is inclosed in the air-tight oasing or jacket I).

c is the inlet connection for the water-jacket b, and d the outlet connection for the tube a, both these connections passing through the casing b in an air-tight manner.

' e e are the wires, which are coiled around the tube a and which enter and pass out of the air-tight casing 19 by the tube f, which enables a hermetic joint to be obtained. With this construction of apparatus water is allowed to enter the jacket I) through the inlet 0 and after filling the same passes into the tube a through the pipe 0 and passes out at the outlet cl. During its passage through the apparatus the water is heated by the electric current from any suitable source of energy, which flows through the wires 6 and heats them, and consequently the tube a and the jacket I), through which the wateris flowing.

In Fig. 2 I have shown a form of apparatus wherein a number of tubes at are employed, the said tubes running lengthwise of the easing 1) and penetrating the ends of the said casing by hermetic joints. This form of the apparatus is designed to be immersed in the water to be heated. The air can be withdrawn from the jacket or casing 12 by any suitable means, and at g I have indicated a valve for the attachment of the pump or other fitting.

Figs; 3 and 4; show a form of the apparatus wherein internal water-jackets h h are employed in lieu of the tubes a. These jackets h h are annular in shape and open top and bottom into trays 'i, (see Fig. 3,) with which the outlet-pipe d and the inlet-pipe c are respectively connected. jj are the heating-wires, which are passed longitudinally down the said jackets, as clearly shown.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is- 1. In an electric water-heater, the combination with a vacuum -chamber provided with water-passages within the same but not in communication with said chamber and'electrio heating-wires within said Vacuum-chain ber, adjacent to but exterior to the waterexterior to and adjacent to said water-conducting devices and insulating material interposed between said wires and said waterconducting devices whereby said wires and the water in said conducting devices can be heated to a higher temperature than would be possible if said wires were exposed to the air, substantially as described.

JOHN WILLIAM EWART. Witnesses J OHN E. BONSFIELD, O. G. REDFERN. 

